libcamera: ipc_unixsocket: Use UniqueFD for a file descriptor

IPCUnixSocket::create() creates two file descriptors. One of
them is stored in IPCUnixSocket and the other is returned to a
caller. This clarifies the ownership using UniqueFD.

Signed-off-by: Hirokazu Honda <hiroh@chromium.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Hirokazu Honda <hiroh@chromium.org>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>

test/ipc/unixsocket_ipc.cpp

@@ -49,9 +49,9 @@ public:
 		ipc_.readyRead.connect(this, &UnixSocketTestIPCSlave::readyRead);
 	}
 
-	int run(int fd)
+	int run(UniqueFD fd)
 	{
-		if (ipc_.bind(fd)) {
+		if (ipc_.bind(std::move(fd))) {
 			cerr << "Failed to connect to IPC channel" << endl;
 			return EXIT_FAILURE;
 		}
@@ -222,9 +222,9 @@ int main(int argc, char **argv)
 {
 	/* IPCPipeUnixSocket passes IPA module path in argv[1] */
 	if (argc == 3) {
-		int ipcfd = std::stoi(argv[2]);
+		UniqueFD ipcfd = UniqueFD(std::stoi(argv[2]));
 		UnixSocketTestIPCSlave slave;
-		return slave.run(ipcfd);
+		return slave.run(std::move(ipcfd));
 	}
 
 	UnixSocketTestIPC test;